With an over increasing number of different sized and shaped boats, the contemporary trailers have tended to develop an ever increasing arrangement of bow and stern supports for accommodating the great variety of trailers. Proper distribution of the weight of the trailer on the frame such that pressure on the tongue will accommodate a balanced connection to the prime mover has been attempted by having one or more stationary keel rollers mounted forwardly on the frame, and either bunks or gangs of horizontally and vertically adjustable rollers mounted rearwardly on the frame. Examples of various such arrangements are shown in U.S. Pat. Nos. 2,816,672; 2,948,423; 3,774,790 and 3,917,087.
Nevertheless, the trailer industry has not only not solved the constant problem of ease of adjustment for proper tongue weight distribution, but has exacerbated the problem by proliferation of the types and arrangement of gangs of rollers such that the problem has actually worsened. Further, there have been no improvements of consequence to winch and stand assemblies, fender units, post load guide, and tail light units, all important to the use and safety of this type boat trailer.
Still further, an improved three point support for the keel and hull bottom is necessary to enable a single boat trailer to provide readily available equal weight distribution for the boat, regardless of size and shape, but of course within the parameters of the trailer's capacity, and with a minimum of adjustments.
Lastly, in the forementioned bunks and gangs of rollers, these have required different mounting structures, thus increasing the amount and type of structure required, with all other increases of costs and servicing needs. Standardization of these mounting requirements is necessary.